openwrt/target/linux/mediatek/patches-4.14/0194-pinctrl-mediatek-mt7622-fix-potential-uninitialized-.patch

From cfcb2cc358f3ff466d4c419d8f6fe0263bdc47b1 Mon Sep 17 00:00:00 2001
From: Sean Wang <sean.wang@mediatek.com>
Date: Wed, 10 Jan 2018 00:28:24 +0800
Subject: [PATCH 194/224] pinctrl: mediatek: mt7622: fix potential
 uninitialized value being returned

commit d6ed93551320 ("pinctrl: mediatek: add pinctrl driver for MT7622
SoC") leads to the following static checker warning:

drivers/pinctrl/mediatek/pinctrl-mt7622.c:1419 mtk_gpio_get()
error: uninitialized symbol 'value'.
1412  static int mtk_gpio_get(struct gpio_chip *chip, unsigned int gpio)
1413  {
1414          struct mtk_pinctrl *hw = dev_get_drvdata(chip->parent);
1415          int value;
1416
1417          mtk_hw_get_value(hw, gpio, PINCTRL_PIN_REG_DI, &value);
^^^^^^^^^^^^^^^^
1418
1419          return !!value;
1420  }

The appropriate error handling must be added to avoid the potential error
caused by uninitialized value being returned.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/pinctrl/mediatek/pinctrl-mt7622.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/pinctrl/mediatek/pinctrl-mt7622.c
+++ b/drivers/pinctrl/mediatek/pinctrl-mt7622.c
@@ -1412,9 +1412,11 @@ static struct pinctrl_desc mtk_desc = {
 static int mtk_gpio_get(struct gpio_chip *chip, unsigned int gpio)
 {
 	struct mtk_pinctrl *hw = dev_get_drvdata(chip->parent);
-	int value;
+	int value, err;
 
-	mtk_hw_get_value(hw, gpio, PINCTRL_PIN_REG_DI, &value);
+	err = mtk_hw_get_value(hw, gpio, PINCTRL_PIN_REG_DI, &value);
+	if (err)
+		return err;
 
 	return !!value;
 }